Unit Cell Titanium Casting

ABSTRACT

A system ( 5 ) and method ( 800 ) for unit cell casting of titanium or titanium-alloys is disclosed herein. The system ( 5 ) comprises an external chamber ( 45 ), a crucible ( 10 ) positioned within the external chamber ( 45 ), an induction coil ( 15 ) positioned around the crucible, an internal chamber ( 40 ) positioned within the external chamber ( 45 ), and a mold ( 30 ) positioned within the internal chamber ( 40 ). The external chamber ( 45 ) is evacuated and a pressurized gas is injected into the evacuated external chamber ( 45 ) to create a pressurized external chamber ( 45 ). An ingot ( 20 ) is melted within the crucible utilizing induction heating generated by the induction coil ( 15 ). The internal chamber ( 40 ) is evacuated to create an evacuated internal chamber ( 40 ). The titanium alloy material of the ingot ( 20 ) is completely transferred into the mold ( 30 ) from the crucible ( 10 ) using a pressure differential created between the external chamber ( 45 ) and the internal chamber ( 40 ).

CROSS REFERENCES TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional PatentApplication No. 62/372626, filed on Aug. 9, 2016, which is herebyincorporated by reference in its entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to precision titanium casting. Morespecifically, the present invention relates to an apparatus and methodfor precision titanium casting utilizing induction heating.

Description of the Related Art

Various methods of titanium casting are well-known. One such method isinvestment casting which involves a lost wax procedure.

Vacuum electric arc smelting is another method in which a titanium ingotis melted by substantial heat generated by mutual discharging in a highcurrent state by respectively using a titanium ingot crucible and awater-cooled copper crucible as a positive electrode and a negativeelectrode, thereby forming a molten liquid metal in the crucible andcompleting the casting of the titanium.

Another method is vacuum induction smelting in which an induction coilis wrapped outside a split-type water-cooled copper crucible. Theelectromagnetic force generated by the induction coil passes through anonmetal isolation portion between splits of the copper crucible andthen acts on a titanium ingot placed inside the crucible. Then themolten metal forms a molten metal liquid inside the crucible and thecasting of the titanium is completed.

Vacuum induction smelting and vacuum electric arc smelting require theuse of a water-cooled copper crucible which results in the loss ofsubstantial heat. The actual power consumed is very little (only 20% to30% of the power actually acts on the titanium). Furthermore, thepreparation of the molding shell is very complex and time consuming,which adds to the costs. In the traditional casting technology, theoperation time of a single furnace is usually 60 to 80 minutes, and theloading and discharge process requires the coordination of many people.In the traditional casting technology, the process from the preparationof the wax pattern to the clearing of the molding shell can take tendays.

Titanium is an extremely reactive metal. During melting via traditionalcasting processes, a water cooling environment is required. The moltentitanium liquid will come into direct contact with water if the cruciblecracks, resulting in a fierce reaction, or even explosion, which poses agreat threat to production safety.

To solve the above problems, a new kind of titanium alloy inductionmelting vacuum suction casting device is urgently needed, to solve theproblems with existing titanium alloy casting, such as low efficiency,high cost, complicated technology, heavy workload, difficulty withpreparing high-quality molding shells, long cycle and potential hazard.

BRIEF SUMMARY OF THE INVENTION

Utilizing the two chamber casting system, one of the primary tenets isthe use of a pressure differential in order to assist the evacuation ofmaterial from the crucible into the pattern mold. In order to trulyoptimize the filling of complex geometries, the physical properties ofresulting parts, and the efficiency of the equipment, it is beneficialto vary the pressure differential utilized during the casting sequence.Optimally, the beginning of the cycle will have a minimal pressuredifferential between the outer chamber (containing the crucible) and theinner chamber (containing the pattern mold). This pressure differentialis achieved through the use of a vacuum (to remove Oxygen and reducepressure) and Argon (to replace any remaining Oxygen and increasepressure). Immediately prior to crucible evacuation the pressure in theinner chamber would be decreased; this will allow for additionalpressure-assisted transition in order to allow the filling of complexgeometries, while minimizing turbulent flow of molten Titanium, and alsominimizing overall equipment cycle times.

One aspect of the present invention is a method for unit cell casting oftitanium or titanium-alloys. The method monitoring a pressure of aninternal chamber utilizing a first vacuum gauge. The method alsoincludes monitoring a pressure of an external chamber utilizing a secondvacuum gauge. The method also includes transmitting the pressure of theinternal chamber and the pressure of the external chamber to aprogrammable logic controller (PLC. The method also includes evacuatingan external chamber to create an evacuated external chamber wherein aceramic crucible containing a titanium alloy ingot is positionedtherein. The method also includes evacuating the internal chamber tocreate an evacuated internal chamber. The method also includes meltingthe titanium alloy ingot within the ceramic crucible utilizing inductionheating generated by an induction coil positioned around the ceramiccrucible. The method also includes injecting a pressurized gas into theevacuated external chamber to create a pressurized external chamber. Themethod also includes transferring the completely melted titanium alloymaterial into the mold from the crucible using a maximum pressuredifferential created between the external chamber and the internalchamber. The pressure of the internal chamber and the pressure of theexternal chamber are monitored and communicated to the PLC during thecasting process, and wherein the PLC controls the casting process basedon the pressure of the internal chamber and the pressure of the externalchamber.

Another aspect of the present invention is a system method for unit cellcasting of titanium or titanium-alloys. The system comprises an externalchamber, a ceramic crucible positioned within the external chamber, aninduction coil positioned around a bottom section of the ceramiccrucible, an internal chamber positioned within the external chamber,and a mold positioned within the internal chamber. A first vacuum gaugepositioned within the internal chamber. A second vacuum gauge positionedwithin the external chamber. A PLC in communication with the firstvacuum gauge, the second vacuum gauge, and the induction coil. Theexternal chamber is evacuated to create an evacuated external chamberwherein the ceramic crucible contains a titanium alloy ingot positionedtherein. The internal chamber is evacuated to create an evacuatedinternal chamber. The titanium alloy ingot is melted within the ceramiccrucible utilizing induction heating generated by the induction coilpositioned around the ceramic crucible, wherein a pressure differentialbetween the external chamber and the internal chamber is at a minimum. Apressurized gas is injected into the evacuated external chamber tocreate a pressurized external chamber. The titanium alloy material iscompletely transferred into the mold from the crucible using a maximumpressure differential created between the external chamber and theinternal chamber. The pressure of the internal chamber and the pressureof the external chamber are monitored and communicated to the PLC duringthe casting process, and wherein the PLC controls the casting processbased on the pressure of the internal chamber and the pressure of theexternal chamber.

The pressurized gas is preferably argon. The mold is preferably coveredin a kaolin wool insulating material. The mold is preferably for athin-walled golf club head. The mold is alternatively for an articlehaving a wall thickness less than 0.250 inch. The induction melting timepreferably ranges from 30 seconds to 90 seconds. The ceramic crucible ispreferably composed of two yttria-based primary crucible layers, whereina first primary crucible layer has a thickness ranging from 0.010 inchto 0.060 inch, and a second primary crucible layer has a thicknessranging from 0.001 inch to 0.020 inch. The ceramic crucible furthercomprises a silica based backup layer. The induction coil is preferablypositioned around a bottom section of the ceramic crucible. Theinduction coil is alternatively positioned around an upper section ofthe ceramic crucible.

Having briefly described the present invention, the above and furtherobjects, features and advantages thereof will be recognized by thoseskilled in the pertinent art from the following detailed description ofthe invention when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is an illustration of a unit-cell casting system.

FIG. 2 is an isolated view of an interior chamber, crucible, inductioncoils and mold of the unit-cell casting system, showing placement of theinduction coils at a lower section of the crucible.

FIG. 2A is an isolated view of an interior chamber, crucible, inductioncoils and mold of the unit-cell casting system, showing placement of theinduction coils at an upper section of the crucible.

FIG. 2B is an isolated view of an interior chamber, crucible, inductioncoils and mold of the unit-cell casting system, showing an insulationmaterial wrapped around the mold.

FIG. 3A is an illustration of a technician pre-heating a mold in anoven.

FIG. 3B is an illustration of a technician attaching the pre-heated moldto a lid of the internal container.

FIG. 3C is an illustration of a technician attaching the lid to theinternal container.

FIG. 3D is an isolated view of the internal container.

FIG. 3E is an isolated view of the lid of the internal container.

FIG. 3F is an isolated view of the internal chamber of the internalcontainer showing infrared heaters.

FIG. 4 is an illustration of a unit-cell casting system during anexternal chamber evacuation step.

FIG. 4A is an illustration of a unit-cell casting system during anexternal chamber pressurization step.

FIG. 4B is an illustration of a unit-cell casting system during an ingotmelting step.

FIG. 5 is an illustration of a PLC unit and computer for a unit cellcasting system.

FIG. 6 is a block diagram of a unit cell casting method.

FIG. 7 is an isolated view of a crucible for a unit cell casting system.

FIG. 8 is a flow chart of a method for unit cell titanium casting.

FIG. 9 is a flow chart of a method for unit cell titanium casting.

FIG. 10 is a flow chart of a method for unit cell titanium casting.

FIG. 11 is an illustration of a PLC unit, an operator's computer for aunit cell casting system, an internal chamber with monitoringconnections.

FIG. 12 is an illustration of a PLC unit, an operator's computer for aunit cell casting system, an internal chamber with monitoringconnections.

FIG. 13 is an isolated bottom plan view of an iris gate between thecrucible and the mold.

FIG. 14 is an isolated bottom plan view of a scissor gate between thecrucible and the mold, with the scissor gate partially closed.

FIG. 15 is an isolated bottom plan view of a gate with two doors betweenthe crucible and the mold.

FIG. 16 is an isolated bottom plan view of a sliding gate between thecrucible and the mold.

FIG. 17 is an illustration of a PLC unit, an operator's computer for aunit cell casting system, and a crucible over a connection with a gatethat is operated by the PLC.

DETAILED DESCRIPTION OF THE INVENTION

During the casting process it is critical to ensure that the material beheated sufficiently and consistently in order to ensure proper flow intothe pattern mold. Especially with the use of a bottom-fed/gravity flowsystem, having the ability to control the pour time will allow foroptimum material properties in the finished part. In order to achievethis, a mechanical door or gate is utilized to evacuate the meltingcrucible at precisely the correct (and repeatable) moment during thecycle. The mechanics of the door itself are designed in variousembodiments; sliding, scissor, iris, etc. as long as it is able toretain the material and provide a vacuum seal. This door is controlledthrough the use of a Programmable Logic Controller (PLC) and ispreferably actuated based on time, temperature, or pressure of thesystem. The use of this feature allows for precise evacuation timesproviding consistent and optimum part quality.

As shown in FIG. 1, a unit cell titanium casting system 5 comprises anexternal container 44, an internal container 39, a vacuum mechanism 60,a crucible 10, an induction coil 15, a coil electrical generationmechanism 25, and a mold 30. The external container 44 defines anexternal chamber 45. The internal container 39 defines an internalchamber 40. The vacuum mechanism 60 includes a vacuum line 71, a vacuumconnector 70 and pressure gauges 75 a and 75 b. The vacuum mechanism 60is utilized to evacuate and pressurize the external chamber 45 and theinternal chamber 40 in order to create a pressure differential betweenthe internal chamber 40 and the external chamber 45.

The crucible 10 is preferably composed of a ceramic material. In a mostpreferred embodiment, the crucible 10 is composed of a first layer 11 a,a second layer 11 b and a silica based third layer 11 c, as shown inFIG. 7. A metal ingot 20 is placed within the interior of the crucible10. The metal ingot 20 is preferably a titanium alloy material. Thevolume of the crucible 10 preferably corresponds to the amount of metalnecessary for forming the article. The interior of the crucible 10preferably has a diameter ranging from 15 centimeters (“cm”) to 90 c m,more preferably from 35 cm to 60 cm. A height of the crucible 10preferably ranges 30 cm to 200 cm, and more preferably from 60 cm to 100cm.

A connection nozzle 27 is connected between a bottom opening (not shown)of the crucible 10 and an opening to the mold 30. The connection nozzle27 allows the melted metal material from the ingot 20 to flow into themold 30 for casting of the article. Specifically, the size of connectionnozzle 27 is determined based on the size and shape of the cavity of themold 30, and is preferably from 5 cm to 100 cm, and more preferably from15 cm to 50 cm.

The induction coil 15 is wrapped around the crucible 10. The inductioncoil 15 is energized to generate an electromagnetic force to melt themetal ingot 20 (e.g., titanium alloy ingot) within the crucible 10. Thecoil electrical generation mechanism 25 provides the electricity to theinduction coil 15. As shown in FIG. 2, the induction coil 15 is wrappedaround a bottom section 10 b of the crucible 10. This melts the bottomof the ingot 20 first. As shown in FIG. 2A, the induction coil 15 iswrapped around an upper section 10 a of the crucible 10. This melts thetop of the ingot 20 first.

In order to optimize the ability of the target material to seal aroundthe port of a ceramic crucible 10, the induction coil 15is preferablycentered on the upper third of the ingot 20. This positioning allows theinduction coil 15 to first act on the upper portion of the ingot 20(melting the material from the top down), causing molten material tocascade around the still-solid ingot 20 and forming a seal before theelectromagnetic forces of the induction coil 15 affect the remainingmaterial.

Alternatively, in order to fully utilize the electromagnetic forces ofthe induction coil 15, to include the electromagnetic stirring of themelt, the induction coil 15 is positioned towards the bottom 10 b of theceramic crucible 10. This positioning allows for a uniform melt asmolten material cascades onto itself and also increased homogeneity ofthe pour as the electromagnetic forces can better act on the moltenmaterial prior to it being evacuated from the crucible 10.

Melting of the ingot 20 of titanium alloy is carried out in a vacuumcondition for induction melting. The induction coil 15 is connected tothe coil electrical generation mechanism 25.

The ceramic crucible 10 is utilized for vacuum induction melting of thetitanium alloy. The ceramic material does not interfere with thefielding effect of the electromagnetic force, and the electro-magneticinduction energy generated by the induction coil 15 is fully focused onmelting the ingot of titanium alloy.

In an embodiment shown in FIG. 2B, an insulating material 31 is wrappedaround the mold 30. During casting pattern molds are preheated prior touse in order to improve the flow of material into the mold itself and tobetter allow the mold 30 to fill completely. Due to the nature oftitanium materials, and the melting process itself, the more that heatloss is minimized, the greater time the material has to flow and fillthe mold 30 prior to solidification. To this end, pattern mold heat isretained through the use of an insulating material 31 (e.g.: Kaolinwool) thereby extending the useful period of the mold 30 prior to thepour and allowing for better fill, including filling of more difficultmolds (e.g., thin walled castings).

As shown in FIGS. 3A, 3B, 3C, 3D and 3E, the mold 30 is preheated in anoven 80. During unit cell casting, pattern molds 30 are preheated priorto use in order to improve the flow of material into the mold 30 itselfand to better allow the mold 30 to fill completely. Due to the nature oftitanium materials, and the melting process itself, there is a likelycorrelation between the temperature of the mold 30 and the ability tofill complex and/or thin walled pattern molds 30. Temperatures testinginclude 1050° C., 1060° C., 1100° C., 1150° C., 1200 ° C., 1250° C. and1260° C. The pre-heated mold is removed from the 80 and attached to alid 35 of the internal container 39.

In an alternative embodiment shown in FIG. 3F, infrared heaters 50 a and50 b are used to maintain the heat of the mold 30 within the internalchamber 40. Due to the nature of titanium materials, and the meltingprocess itself, the more that heat loss is minimized, the greater timethe material can flow and fill the mold 30 prior to solidification. Tothis end, pattern mold heat is retained through the use of infraredheaters 50 a and 50 b placed within the internal walls of the internalchamber 40 of the internal container 39 in order to minimize patternmold cool down and improve the ability to cast complex and/orthin-walled parts.

FIGS. 4, 4A and 4B illustrate the casting process using a pressuredifferential between the external chamber 45 and the internal chamber 40to assist in the flow of melted titanium alloy materials into a mold 30.

FIG. 5 illustrates a programmable logic computer (“PLC”) and operatorcomputer 91 utilized with the unit cell casting system 5.

FIG. 6 is a block diagram of a unit cell casting method 600. At step601, an ingot 20 is prepared for casting. The single ingot 20 isutilized to manufacture a single article such as a golf club head 29. Asopposed to manufacturing multiple articles in a single process, whichresults in the loss of material, the present invention manufactures onlya single article in each process. At step 602, the mold 30 is preheatedin an oven. At step 603, the external chamber 45 is evacuated. At step604, the external chamber 45 is pressurized with an argon gas. At step605, the internal chamber 40 is evacuated. At step 606, the inductioncoil 15 is energized and at step 607 the ingot 20 is melted within thecrucible 10. At the step 608, the melted material flows into mold 30. Atstep 609, the de-molding process occurs. At step 610, the article (golfclub head) 29 is finished. A frequency generated in the induction coilranges from 1 kilo-Hertz to 50 kilo-Hertz, and a power ranges from 15kilo-Watts to 50 kilo-Watts. An atmospheric pressure of the evacuatedinternal chamber ranges from 3×10⁻² atmosphere to 9.87×10⁻⁷ atmosphere.An atmospheric pressure of the evacuated internal chamber ranges from9.87×10⁻⁷ atmosphere to 9.87×10⁻¹³ atmosphere.

As shown in FIG. 7, the first layer 11 a and the second layer 11 b arepreferably composed of yttrium oxide and other materials. Yttrium oxideis highly inert to titanium in a high-temperature environment resultingin no chemical reaction between the two materials. Yttrium oxide alsoisolates the ceramic material from the titanium during the meltingprocess to prevent reaction between them to ensure the smooth melting ofthe titanium-alloy. The third layer 11 c of the crucible 10 ispreferably composed of silicon dioxide and other materials. The silicondioxide resists the metallic expansion and thermal stress during themelting process to ensure strength of the crucible.

A preferred thickness of the first layer 11 a is from 0.5 mm to 1.5 mmand the preferred thickness range of the crucible 10 is from 5 mm to 15mm.

A method 800 for unit cell casting of titanium or titanium-alloys isshown in FIG. 8. At block 801, a pressure of an internal chamber ismonitored utilizing a first vacuum gauge. At block 802, a pressure of anexternal chamber is monitored utilizing a second vacuum gauge. At block803, the pressure of the internal chamber and the pressure of theexternal chamber are transmitted to a programmable logic controller(PLC). At block 804, a mold is positioned within the internal chamber.At block 805, an external chamber is evacuated to create an evacuatedexternal chamber having a pressure no greater than 3×10⁻² atmosphere,wherein a ceramic crucible containing a titanium alloy ingot ispositioned therein. At block 806, the internal chamber is evacuated tocreate an evacuated internal chamber having a pressure no greater than3×10⁻² atmosphere, wherein the external chamber and the internal chamberhave an equal pressurization. At block 807, the titanium alloy ingot ismelted within the ceramic crucible utilizing induction heating generatedby an induction coil positioned around the ceramic crucible. At block808, the completely melted titanium alloy material is transferred intothe mold from the crucible using a pressure equalization between theexternal chamber and the internal chamber. A pressure equalization ismaintained between the external chamber and the internal chamber duringthe melting of the titanium alloy ingot. The pressure of the internalchamber and the pressure of the external chamber are monitored andcommunicated to the PLC during the casting process, and wherein the PLCcontrols the casting process based on the pressure of the internalchamber and the pressure of the external chamber.

A method 900 for unit cell casting of titanium or titanium-alloys isshown in FIG. 9. At block 901, a pressure of an internal chamber ismonitored utilizing a first vacuum gauge. At block 902, a pressure of anexternal chamber is monitored utilizing a second vacuum gauge. At block903, the pressure of the internal chamber and the pressure of theexternal chamber are transmitted to a programmable logic controller(PLC). At block 904, a mold is positioned within the internal chamber.At block 905, an external chamber is evacuated to create an evacuatedexternal chamber having a pressure no greater than 3×10⁻² atmosphere,wherein a ceramic crucible containing a titanium alloy ingot ispositioned therein. At block 906, the internal chamber is evacuated tocreate an evacuated internal chamber having a pressure no greater than3×10⁻² atmosphere, wherein the external chamber and the internal chamberhave an equal pressurization. At block 907, the titanium alloy ingot ismelted within the ceramic crucible utilizing induction heating generatedby an induction coil positioned around the ceramic crucible. At block908, a pressurized gas is injected into the evacuated external chamberto create a pressurized external chamber with a pressure in excess of 1atm, wherein the pressure differential between the external chamber andthe internal chamber is maximized. At block 909, the completely meltedtitanium alloy material is transferred into the mold from the crucibleusing a pressure equalization between the external chamber and theinternal chamber. A high pressure differential in maintained between theexternal chamber and the internal chamber during the transfer of themelted titanium alloy material. The pressure of the internal chamber andthe pressure of the external chamber are monitored and communicated tothe PLC during the casting process, and wherein the PLC controls thecasting process based on the pressure of the internal chamber and thepressure of the external chamber.

A method 1000 for unit cell casting of titanium or titanium-alloys isshown in FIG. 10. At block 1001, a mold is positioned within an internalchamber of a casting chamber. At block 1002, an external chamber isevacuated to create an evacuated external chamber wherein a ceramiccrucible containing a titanium alloy ingot is positioned therein. Atblock 1003, the internal chamber is evacuated to create an evacuatedinternal chamber having a pressure no greater than 3×10⁻² atmosphere. Atblock 1004, the titanium alloy ingot is melted within the ceramiccrucible utilizing induction heating generated by an induction coilpositioned around the ceramic crucible, wherein the external chamber andthe internal chamber are at an equal pressurization. At block 1005, apressurized gas is injected into the evacuated external chamber tocreate a pressurized external chamber with a pressure in excess of 1atmosphere. At block 1006, a high pressure differential is utilizedbetween the external chamber and the internal chamber to flow thecompletely melted titanium alloy material into the mold from thecrucible.

FIG. 11 illustrates a PLC 90, an operator's computer 91 and an apparatus5 for a system for unit cell titanium casting.

FIG. 12 illustrates a PLC 90, an operator's computer 91 and an internalchamber with an optical pyrometer for a system for unit cell titaniumcasting. The optical pyrometer monitors the temperature of the internalchamber.

FIG. 13 is an isolated bottom plan view of an iris gate 185 between thebottom of the crucible 10 d and the mold. The iris gate 185 is attachedto the connection nozzle 27. Two hinges 185 a and 185 b allow for theswing opening of the iris gate body 185 c to permit the flow of themelted titanium into the mold.

FIG. 14 is an isolated bottom plan view of a scissor gate 186 betweenthe bottom of the crucible 10 d and the mold, with the scissor gatepartially closed. The scissor gate 186 is attached to the connectionnozzle 27. The scissor gate 186 compresses inward to permit the flow ofthe melted titanium into the mold.

FIG. 15 is an isolated bottom plan view of a gate 187 between the bottomof the crucible 10 d and the mold. The gate 187 is attached to theconnection nozzle 27 by hinges 187 a-d. Two doors 187 e and 187 f swingopen to permit the flow of the melted titanium into the mold.

FIG. 16 is an isolated bottom plan view of a sliding gate 188 betweenthe bottom of the crucible 10 d and the mold. The sliding door 188 a isin an open position.

FIG. 17 is an illustration of a PLC unit, an operator's computer for aunit cell casting system, and a crucible over a connection with a gate185 that is operated by the

PLC 90.

Those skilled in the pertinent art will recognize that materials otherthan titanium and titanium alloy may be cast in the unit cell castingsystem without departing from the scope and spirit of the presentinvention.

From the foregoing it is believed that those skilled in the pertinentart will recognize the meritorious advancement of this invention andwill readily understand that while the present invention has beendescribed in association with a preferred embodiment thereof, and otherembodiments illustrated in the accompanying drawings, numerous changes,modifications and substitutions of equivalents may be made thereinwithout departing from the spirit and scope of this invention which isintended to be unlimited by the foregoing except as may appear in thefollowing appended claims. Therefore, the embodiments of the inventionin which an exclusive property or privilege is claimed are defined inthe following appended claims.

We claim as our invention the following:
 1. A method for unit cellcasting of titanium or titanium-alloys, the method comprising:positioning a mold within an internal chamber, wherein a pressuredifferential between the internal chamber and an external chamber is ata minimum; evacuating an external chamber to create an evacuatedexternal chamber wherein a ceramic crucible containing a titanium alloyingot is positioned therein; evacuating the internal chamber to createan evacuated internal chamber having a pressure no greater than 3×10⁻²atmosphere, wherein a pressure differential between the external chamberand the internal chamber is at minimum; injecting a pressurized gas intothe evacuated external chamber to create a pressurized external chamberwith a pressure in excess of 1 atm, wherein the pressure differentialbetween the external chamber and the internal chamber is maximized;melting the titanium alloy ingot within the ceramic crucible utilizinginduction heating generated by an induction coil positioned around theceramic crucible; opening a mechanical gate below the ceramic crucibleimmediately after the titanium alloy ingot is completely melted withinthe ceramic crucible; transferring the completely melted titanium alloymaterial into the mold from the crucible using a pressure differentialcreated between the external chamber and the internal chamber; wherein ahigh pressure differential in maintained between the external chamberand the internal chamber during the transfer of the melted titaniumalloy material; wherein the PLC controls the opening of the mechanicalgate to correspond to the complete melting of the titanium alloy ingotin the ceramic crucible; wherein the pressure of the internal chamberand the pressure of the external chamber are monitored and communicatedto the PLC during the casting process, and wherein the PLC controls thecasting process based on the pressure of the internal chamber and thepressure of the external chamber.
 2. The method according to claim 1wherein the pressurized gas is argon.
 3. The method according to claim 1wherein a frequency generated in the induction coil ranges from 1kilo-Hertz to 50 kilo-Hertz, and a power ranges from 15 kilo-Watts to 50kilo-Watts.
 4. The method according to claim 1 wherein an atmosphericpressure of the evacuated internal chamber ranges from 3×10⁻² atmosphereto 9.87×10⁻⁷ atmosphere.
 5. The method according to claim 1 wherein themechanical gate provides a vacuum seal when in the closed position toseal the external chamber.
 6. The method according to claim 1 whereinthe mechanical gate is one of a sliding gate, a scissor gate and an irisgate.
 7. The method according to claim 1 wherein the PLC determines whento melt the titanium alloy based on the pressures of the internalchamber and the external chamber.
 8. The method according to claim 7wherein the PLC determines when to change the pressure of internalchamber and the external chamber.
 9. The method according to claim 1wherein an atmospheric pressure of the evacuated internal chamber rangesfrom 9.87×10⁻⁷ atmosphere to 9.87×10⁻¹³ atmosphere
 10. A system methodfor unit cell casting of titanium or titanium-alloys, the systemcomprising: an external chamber having a mechanical gate; a ceramiccrucible positioned within the external chamber; an induction coilpositioned around a bottom section of the ceramic crucible; an internalchamber positioned within the external chamber; and a mold positionedwithin the internal chamber; a first vacuum gauge positioned within theinternal chamber; a second vacuum gauge positioned within the externalchamber; a PLC in communication with the first vacuum gauge, the secondvacuum gauge, and the induction coil; wherein a minimal pressuredifferential in maintained between the external chamber and the internalchamber prior to the melting of the titanium alloy ingot; wherein thepressure of the internal chamber and the pressure of the externalchamber are monitored and communicated to the PLC during the castingprocess, and wherein the PLC controls the casting process based on thepressure of the internal chamber and the pressure of the externalchamber; wherein the external chamber is evacuated to create anevacuated external chamber wherein the ceramic crucible contains atitanium alloy ingot positioned therein; wherein a pressurized gas isinjected into the evacuated external chamber to create a pressurizedexternal chamber; wherein the titanium alloy ingot is melted within theceramic crucible utilizing induction heating generated by the inductioncoil positioned around the ceramic crucible; wherein the internalchamber is evacuated to create an evacuated internal chamber; whereinthe PLC controls the opening of the mechanical gate to correspond to thecomplete melting of the titanium alloy ingot in the ceramic crucible;wherein the titanium alloy material is completely transferred into themold from the crucible using a maximum pressure differential createdbetween the external chamber and the internal chamber.
 11. A method forunit cell casting of titanium or titanium-alloys, the method comprising:evacuating an external chamber to create an evacuated external chamberwherein a ceramic crucible containing a titanium alloy ingot ispositioned therein; evacuating the internal chamber to create anevacuated internal chamber having a pressure no greater than 3×10⁻²atmosphere; melting the titanium alloy ingot within the ceramic crucibleutilizing induction heating generated by an induction coil positionedaround the ceramic crucible, wherein the external chamber and theinternal chamber are at an equal pressurization; injecting a pressurizedgas into the evacuated external chamber to create a pressurized externalchamber with a pressure in excess of 1 atmosphere, wherein the pressuredifferential is at a maximum; opening a mechanical gate below theceramic crucible immediately after the titanium alloy ingot iscompletely melted within the ceramic crucible; and utilizing a highpressure differential between the external chamber and the internalchamber to flow the completely melted titanium alloy material into themold from the crucible.
 12. The method according to claim 11 wherein thepressurized gas is argon.
 13. The method according to claim 11 wherein afrequency generated in the induction coil ranges from 1 kilo-Hertz to 50kilo-Hertz, and a power ranges from 15 kilo-Watts to 50 kilo-Watts. 14.The method according to claim 11 wherein an atmospheric pressure of theevacuated internal chamber ranges from 3×10⁻² atmosphere to 9.87×10⁻⁷atmosphere.
 15. The method according to claim 11 wherein the mechanicalgate is one of a sliding gate, a scissor gate and an iris gate.
 16. Themethod according to claim 11 wherein the internal chamber is preheatedat a temperature ranging from 1150° C. to 1250° C.
 17. The methodaccording to claim 11 wherein a PLC determines when to melt the titaniumalloy based on the pressures of the internal chamber and the externalchamber.
 18. The method according to claim 11 wherein the PLC determineswhen to change the pressure of internal chamber and the externalchamber.
 19. The method according to claim 11 wherein an atmosphericpressure of the evacuated internal chamber ranges from 9.87×10⁻⁷atmosphere to 9.87×10⁻¹³ atmosphere
 20. The method according to claim 11wherein the mechanical gate provides a vacuum seal when in the closedposition to seal the external chamber.